Carburetor



Sept. 8, 1931. 5.` H sKlNNER GARBURETOR Filed April 24, 1926 l a@ 5562 ll @Q j ,I j G 7.2.! u 2 1 www 42].. Q 1%. I fp@ o o 7 l z i j f PatentedSept. 8, 1931 Unirse STATES GEORGE HERBERT SKINNER, OF EALING, LONDON,ENGLAND, ASSIGNOR TO PANY, LIMITED, OF LONDON, ENGLAND PATENT OFFICE S.U. COM- CARBURETOR Application `tiled April 24, '1926, Serial No.104,254, and in Great Britain April 30, 1925.

This invention relates to carburetors and has particular though notexclusive reference to -carburetors of the type in which a piston valvefor controlling the main air passage and carrying' a needlev valve forcontrolling the liquid fuel supply is under the influence of and isoperated by engine suction.

According to one feature of the present invention the said air valvecarrying the y needle valve is formed in one with or is directly securedto a piston (hereinafter referred to as the suction disc) which isadapted to work in a suction chamber so that it can be operated to raisethe piston valve by the 15 enginesuction. By providing` a combinedpiston valve and suction disc, the usual spindle or rod'which incarburetors of the kind hereinbefore referred to is located between thesuction disc and the piston valve and also the bearing therefor areavoided. A rod may extend upwardly beyond the aforesaid suction disc soas to slidably fit in a sleeve or bearing formed on the upper part j ofthe said suction chamber, the said sleeve or bearing having a restrictedorifice for the escape of air so that a kind of dashpot action isafforded when the said rod is moved upwardly due to the combined suctiondisc and the piston valve being raised by the engine 30 suction.Communication between the space above the suction disc in the suctionchamber and hthe engine side of the main passage leading to the engineinduction pipe, may be A, effected through a hole in the aforesaidpiston valve so that the combined suction disc and piston valve can beplaced under the influence of the engine suction during the running ofthe engine, and thereby raised to control the said main passage whilstat the same time 4:0 the needle, valve on the piston valve controls thefuel supply. The movement of the combined suction vdisc and piston valvemay to some extent be controlled or regulated by the f dashpot actionprovided by the aforesaid rod which serves as a plunger withinl itssleeve or bearing and the area of the restricted air orifice is chosenor selected to suit the'particular engine for which the carburetor isintended; or in some cases the said restricted f orifice maybeadjustable.

According to a further feature of the presi cnt invention improved meansare provided to ensure that a fuel tight joint is provided for anadjustable fuel jet tube or nozzle. The

jet tube which is axially adjustable or slidable within a sleeve or thelike is surrounded by washers of cork or other material which areadapted to be compressed around the said tube by spring means preferablyacting in conjunction with bevelled surfaces, the said jet tube havingholestherein through which fuel supplied to thei'nterior of the sleevefrom the oat chamber passes to the jet tube orifice throughwhich theaforesaid nozzle valve passes. i

In order that the said invention may be clearly understood and readilycarried into effect,l the same will now be described more fully withVreference to the accompanying drawings, in which 7 7o Figure l is asectional view of a construction of carburetor embodying theimprovements according to this invention. Figure 2 is a sectional viewtaken on the line 2h2 of Figure 1.

Figure 3 is an enlarged sectional view illustrating the adjustable jettube or nozzle with the associated parts. v

A indicates the main body ofthe carburetor having a mainair passage Aleading to the engine induction pipe and fitted with a throttle Azasshown in Figure B indicates a cover orcap which is secured t0 the mainbody A and constitutes the aforesaid suction chamber. C is the pistonvalve which is slidable in the body A to control the passage A and whichcarries the needle valve D that controls thefuel jet tube or nozzle E.The piston valve C is formed integrally with a suctiondisc or piston Cwhich makes a sliding fit in the cover B forming the suction chamber. Aguide rod or plunger C2 extends upwardly from the lower part of thepiston valve C and'makes va close sliding fit in a sleeve or bearing Bprovided in the cap or cover B forming the suction chamber. The lowerpart of the piston valve is provided with a passage C3 through whichcommunication is established between the interior of the suction chamberabove the sucmi said Washer as shown in Figure 2.

tion disc C and the engine side of the passage A leading to the engineinduction pipe and the space below the suction disc is open to outsideair through a passage A3 (see Figure l). rIhe piston valve C ismaintained with its passage C3 located in the engine side of the mainpassage A by means ot a pin A4 engaging with a slot C4 in the said valveC. The combined piston valve and the suction disc'with the needle valvecan therefore be raised by engine suction to control the passage A andthe fuel jet nozzle E accord.- ing to requirements. The upper end ot"the sleeve B is provided with a screw plug B2 which has a small openingB3 therein that allows air to escapeV from the space above the plungerrod C2 at a more or less restricted rate according to the areaot theorilice. The said plunger rod working in the sleeve with tlie restrictedoritice may serve as a dashpot tro-limit or control the movement of thesuction` disc'and'piston valve as this movement is to some extentregulated or determined by the'sizel ot the orilicek that' may be chosento suit the particular engine toy which thecarburetnr is applied. Anadjustable orifice may` be providedv it desired.

In the example illustrated the jet tube E isslid'abl-y tted in a twopart sleeve'F and F iitted within the lower part otthe main body orcasing A. The lower sleeve portion F which is flangedv aft its upper endis held withinan externally threaded. nut 'G whichisscnewed. intothebody; Arend bears againstl a cork washer Gr through' a` metal2 ringG2 having; bevelled surtace that engages the lower sleeve portion vFretains the upper sleeve portion; F7 1n position around. the

upper end of the jettube which portion F is provided with openings F2that establish Comunication between an. opening Af in themam bodyleading fromf the float chamber' A6 to the interior of the 'lower:sleeve portion F vso that the fuel is supplied to' the ,said interiorofthe sleeve portion F and can: passI through holes E in the jet tube Ewhence-it passes through the orifice controlled by thel needle valve D.Thej et tube mall-esl awfairly closey sliding' lit' inthe lower `end ofthe sleevel portion Fand the upper en'd of the sleeve portion F, and itsslidingY movement can be limited by a liange E thereon engaging with anadjustable nut or abut-mentV F3 screwed on the lower end of the sleeveFA against ay spring F4` that bears against the nut G. In order toprovide a petrol tight` closure torthe adjustable jet tubel FJ, corkwashers Hk surround the jet tube and inthe example shownY are maintainedbetweenY bevelled surfaces on the saidv sleeve portions 'srpringjllzl2which bears-against the said` rings F and F and on rings H by aninterposed 'H so that by reason 'of these said'bevelled surfaces -thecork washers. :are compressed rvIlhe saidv tightly around the said tubeE without however preventing it from being slidably moved to vary theposition of its orifice in relation to the tapered needle valve D. Bythis construction a liquid tight closure is provided Jfor theslidabletube E and it is not necessary to provide light tight closuresbetween the metal surface of the jet tube E and the surrounding portionsot the sleeve parts F and F. Any suitable meansl may 'be provided foradjusting the jet tube E and in the example shown a lever I is pivotedto the end of the tube and to a link I pivotally mounted on the body Athe leverbeing actuated through any appropriate connection. Byadjusting'th'e nut F3f on the sleeve F` the limit oli` inward movementot the jet tube can be varied owing to the flangey E2 on the jet tube Evengaging this nut; andIby this arrangement the` jet tube may beVconveniently set from the exterior'ofv the carlniretory and it. may beadj usted: to provide a suitable-supply offuel for slow running of theengine. Instead of employing ra two par-t sleeve F and F" a singlesleeve may be used-and the body A may bezsuitably` formed: at the upperendv ot the jet tube to receive the cork washer H..

What I claim and desirev to secure by Letters Patent of the4 United.States is l. A carburetor comprising a body having a' straight throughairand mixture passage, a; piston valve vertically movable acrosssaidpassage, a needle valve onf the lower surface of said: piston-valve, a.tuel' jet. nozzle arranged infthe lower part'of said4 passage andVconrtrolled' by saidY needle valve, a suctionpchamber in theupper'part-ofsaidlbod a flangelikeI portion on the .top of said? pistonvalveforming asuction: disc working iii-,said chamber, an upwardly extending;plunger on1 said pistonA valve, a sleeve disposed mainly within .saidsuction chamber and adapted toreceive said.. plunger, 'and 'meansproviding a restrictedfegressof aint-rom the upper part of said sleeve'when said pistonvalve is moved upwardly, said pistonY valve beingprovided with a duct establishing communica-tion between said suctionchamber above said suction disc Iand the'engine side of said passa-ge,and said body` being provided with a duct communicating with theatmosphere below :said suction disc'. a

2. A carburetorcomprising a body having a straight through lairandmixture passage, a piston valve vertically movable across saidvpassage, said piston valve. having a recess therein, a: needle valve onthe lower surface of said-piston-val-ve, a fuel jet nozzle arranged inthe lower part of' said passage and ycontrolledvr byl said needle valve,a suction cham- 'ber' in the upper part of said body, :aflangelikeportion on the top of said piston valve forming :a suction discworking'in Isaid chamber, a plunger extending'upvvardly'from the base ofsaid piston 'valve vinto: said recess, an

internal elongated bearing sleeve Within said suction chamber projectinginto said recess, and means providing a restricted egress of air :fromthe upper part of said sleeve.

3. A carburetor comprising a body having a straight through air andmixture passage, a separate cover member thereon forming a suctionchamber, a piston valve vertically movable across said passage, saidpiston valve having a duct therein, a needle va'lve on said pistonvalve, a fuel jet nozzle arranged in the lower part of said passage andcontrolled by said needle valve, an integral enlarged portion on theupper part of said piston valve working in said suction chamber, aplunger extending upwardly from said piston valve, an internal sleeveintegral with said cover member adapted to receive said plunger, andmeans providing a restricted escape of air from said sleeve When saidpiston valve is caused to move upwardly under the inuence of enginesuction acting on said enlarged part through said duct.

4. A carburetor comprising a body having a straight through air andmixture passage, a separate cover member thereon forming a suctionchamber, a piston valve vertically movable across said passage, saidpiston valve having a recess therein, a needle valve on said pistonvalve, a fuel jet nozzle arranged in the lower part of said passage andcontrolled by said needle valve, an integral enlarged portion on theupper part of said piston valve working in said suction chamber, saidenlarged part surrounding said recess, a plunger extending upwardly outof said recess, an integral sleeve internally disposed in said covermember and projecting into said recess, and means at the upper end ofsaid sleeve, providing a restricted escape of air therefrom, said pistonvalve being provided with a duct establishing communication between saidsuction chamber above said enlarged part and the engine side of the saidpassage, and said body being provided With a duct establishingcommunication between the space belogv said enlarged portion and theatmosp ere.

GEORGE HERBERT SKINNER.

GERTECA'EE 0F CQRREGTEON,

Patent No. 1,822,712. Granted September 8, 1931, to

Genese HERBERT SMNNER.'

It is hereby certified that the aheve numbered` patent was erreneeuslyissued te "S. `U. Company, Limited, ef Landen, England", whereas saidpatent should have been issued to Morris lndnstries, Limited, el Landen,England, as assignee of the entire interest in sai invention, as shownhy the reeerds of assignments in this office; and that the said LettersPatent shenid be read with this correctien therein that the same mayeenlerm te the reeerri ei the case in the Patent Office.

Signed and sealed this l'th clay of November, A.. l). 1931.

M. J. Moore, (Seal) Acting temmissioner of Patents.

